# 获取字典的元素
scores = {'zs': 22, 'ls': 90, 'wz': '88'}
print(scores.get('zs'))
print(scores.get('ll'))  # 返回None
print(scores['zs'])
# print(scores['ll'])     # 报错

print(scores.get('ll', 101))  # key 不存在 并赋予默认值
